Toyota Repair: 2000 Corolla hesitation, maf sensor, question thanks

Question
QUESTION: My friend's 2000 Corolla hesitates bad from a cold start and to a lesser extent after warmed up while accelerating or revving the engine in park with or without the AC engaged. It's pulling 2 codes, p0300 & p0171 The air filter & spark plugs are new. It also shows 1-2 misfire on all four cylinders when revving the engine. Any ideas on what the problem is? Thanks

ANSWER: The p0300 is a random cylinder misfire detected, the p0171 is a lean fuel trim condition which is more than likely caused by the misfire so the misfire should be addressed first. Are there misfire codes p0301,302,303 and 304 also present? If not all then which ones?

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QUESTION: Thanks Ted, but today I took out the MAF sensor and cleaned the 2 little wires way down inside and now the car runs better than it has in a long time. Thanks  for your help.
P.S there were only p0300 & p0171 codes

Answer
You did the right thing, the p0171 code by itself is normally due to a dirty MAF sensor and if it was the only code I would have recommended doing what you did but the fact that it had misfire codes was my primary concern, let me know if i can help in the future.